Maunabo is located on the southeast part of the island. Your best alternatives are the following:
Caja de Muertos: The best snorkeling off the coast of Ponce is on the uninhabited coast island of Caja de Muertos ("Coffin Island"). This isla got its name from an 18th-century French writer who noted that the island's shape resembled a cadaver in a coffin. Over the years there have been fanciful legends about the island, including tales of necrophilia, star-crossed lovers, and, of course, piracy. Several outfits will take you to this remote spot for a full day's outing, with plenty of snorkeling.
La Paguera: The reefs surrounding the offshore cays just off La Paguera in southwest Puerto Rico are another fine spot for snorkeling. Several boat operators right in town will either rent you a boat with a guide or drop you off on one of the islands and return at a pre-arranged timed.
Fajardo: On the eastern coast of Puerto Rico, the clear waters along the beachfront are the best on mainland Puerto Rico for snorkeling. The best beaches here for snorkeling are walking distance from the Seven Seas public beach: Playa Escondido and Playa Convento. The snorkeling at Las Cabezas de San Juan nature refuge is also spectacular.
Of the three alternatives the best is La Parguera.
